An unusual case of Ewing sarcoma: a middle-aged woman with multiple recurrences over 36 years.

Ewing sarcoma (EWS) is a primary bone tumor that most often occurs in the long bones of young patients. EWS is typically an aggressive tumor that is highly sensitive to radiation therapy; recurrences often occur, usually within a year of treatment. We present a case of EWS that first presented in a patient at the age of 40 with extraosseous disease. The patient was treated initially with radiation and surgery. Over the following 36-year period, the tumor recurred once and metastasized twice. The morphologic, immunohistochemical, and cytogenetic features of this tumor were typical of EWS, and the tumor was highly responsive to radiation therapy. The unusually prolonged course in this patient demonstrates significant heterogeneity in the biological behavior of EWS, and the importance of randomized trials in cancer therapy.